                    programming your sirc client
	            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~


Warning: to understand this you need to know perl (the programming
language; type "man perl" for more info on it), and to have read
the README thoroughly.

For a real usable example of sirc script, look at the file n0thing.pl 
(previously zer0.pl); if you wonder how you could do something in sirc 
script, try understanding the functions defined in there.


Functions:

From /loaded scripts and .sircrc.pl, you can define new functions
and give their implementation in perl. 

These scripts are actually files of perl code, and they get loaded
right into sirc's context.

To define a new command, all you need to do is define a sub with the 
name cmd_yourcommandname which does whatever you want it to do, and call 
&addcmd("yourcommandname");

You can also define some help for the command, by calling
&addhelp("yourcommandname", "First line of help\nSecond line of help...");

Your sub gets all of its arguments in the global variable $args 
(unparsed), its own name in $cmd, and the whole command line in $line.

It can also use a number of routines from the sirc client:
  &dosplat;		 turns a * into the current channel name, if it's
  			 the first word of $args
  &getarg;		 to get the first word of $args in $newarg and
  			 the rest in $args
  &yetonearg;		 same thing, removing a trailing : in $args if
  			 there's one
  &eq("txt1", "txt2");   tests case-insensitive equality
  &sl("text");		 to send a line of text to the server (the
			 trailing "\n" gets added automatically)
  &tell("txt");		 sends text to the screen, adding a "\n", and
  			 only if not in silent mode
  &print("txt");  	 sends text to the screen, adding a "\n", regardless
  			 of silent mode
  &getuserline("str", "prompt");
  			 prints "str" on the screen, puts "prompt" as a
			 temporary prompt if using ssfe, and prompts the
			 users for a line, returning it in $_
  &dostatus;	   	 redisplays the status line
  &msg("nck", "msg");	 sends a message, printing it
  &notice("nck", "msg"); sends a notice, printing it
  &say("msg");		 says somethign on the current channel, printing it
  &describe("nck", "msg");  sends a /describe, printing it
  &me("msg");            does an action on the current channel, printing it
  &docommand("command"); interprets a command line as if it were typed at
  			 the keyboard. a *single* leading "/" will 
			 disable alias/function expansion on the 
			 command.
			 *warning* this calls the command dispatcher 
			 recursively from itself, and it's up to *you* 
			 to make sure you don't loop infinitely. perl 
			 being a language with strong and powerful 
			 control structures (unlike ircII...), recursion 
			 at this level should be avoided whenever possible.

And you have access to the following global variables (don't modify them
without really *good* reasons or sirc will get all confused):

  $version		 sirc's version - should always be a number, and
			 never be modified by a user function
  $add_ons		 additional modules loaded; scripts can add a
			 "+scriptname" to it
  $nick			 your current nick
  $ircname		 your ircname - you can change it, it will take effect
			 on the next server reconnect
  $server		 your current server
  $finger		 your reply to /ctcp finger - you can modify this one
  @channels		 list of channels you're on
  $talkchannel		 your current channel (or '' if none)
  %mode			 associative array with the modes of the different
  			 channels we're on. the channel names are all in
			 lower case, and the mode is a string of letters
			 without +'s or -'s, and without 'k' or 'l' either
			 since those are treated separately. the value
			 for channels without any mode is '', while the
			 value for channels we're not on is undef.
  %chankey		 keys to channels, undef if none or we're not on
  			 the channel. channel names are in lower case.
  %limit		 limits to channels, undef if none or we're not
  			 on the channel. channel names in lower case.
  %haveops		 associative array of booleans, true if we have ops
  			 on the channel. channel names are... you know how
  $umode		 user mode, string of letters without +'s or -'s
  $lastmsg		 nick of the person who you last sent a message to
  $query		 whoever you're querying, or '' if no-one
  %aliases		 associative array of defined substitution aliases;
  			 the alias name is in CAPS
  %notify		 associative array of the notify list; the value
  			 for a given nick is 0 for "absent", or the time
			 of the most recent notification for this nick
  $logfile		 name of the log file; you can change this
  $logging		 flag that tells if we're logging or not; don't
			 change it because you'd also need to open/close 
			 the logfile

Warning: functions and hooks should *not* modify the parameters that
are passed to them (i.e. do somethign like $_[1]="some value"); if
they wish to modify local copies of them, they should start with
local($somename1, $somename2)=@_; (replacing "2" with the actual number
of parameters).

Also, if your script is going to use global variables, please make sure 
they're not likely to clash with sirc's own (same goes for file 
descriptor names, and procedures). A good convention would be to give 
all these variables and procedures a name that starts with the script 
name, or with a few letters from it. For example, in n0thing.pl all the 
script's global variables and internal procedures have names that start 
with "n_".

Example, which could be put into a file and /load'ed directly, of
a command that will yeek on a channel if you specify one, and at a
nick if you do too:

~~~~~~~~~~~~~~~~~~~~~~~~~~~ [snip snip] ~~~~~~~~~~~~~~~~~~~~~~~~~~~
sub cmd_yeek {
  &dosplat;		# if the 1st arg is *, replace it with $talkchannel
  &getarg;		# get 1st arg in $newarg
  local($channel)=($talkchannel);	# by default we talk to $talkchannel
  if ($newarg =~ /^[\#\&]/) {		# if the 1st arg starts with # or &
    $channel=$newarg;			# talk there instead
    &getarg;				# and get an extra arg
  }
  if ($newarg) {	# look at whether we specified who we're yeeking at
    &describe($channel, "look at $newarg and *yeeeks*");
  } else {		# or not
    &describe($channel, "*yeeks* at the crowd");
  }
}

# \cb is the way to specify ^B in perl
&addcmd("yeek");
&addhelp("yeek", "Usage: \cbYEEK\cb [<channel>] [<nick>]
Yeeks at the given nickname or at the whole channel.
Examples: /yeek someone
          /yeek * someone
 	  /yeek #channel
 	  /yeek #channel someone");

~~~~~~~~~~~~~~~~~~~~~~~~~~~ [snip snip] ~~~~~~~~~~~~~~~~~~~~~~~~~~~

Hooks: 

From /load'ed scripts, as well as from .sircrc.pl, you have
the possibility to define subs to be called when specified events
occur. This is the equivalent of ircII's /on's.

To declare a hook, you must define a subroutine called "hook_somename"
which does whatever you want done when a hook of type "hook_type" is
triggered, and then call &addhook("hook_type", "somename");

To remove a hook, you call &remhook("hook_type", "somename");

Numeric hooks are also available, for every 3-digit number; to declare
one of those, define a soubroutine called "hook_somename" which does
what you want, and call &addhook("xxx", "somename"), where xxx is the
number of the numeric reply. To remove one of these, you call
&remhook("xxx", "somename");

Subs called from hooks have access to the same functions and variables
listed above for functions, plus a few specific ones (wherever
applicable):

$who		is the nick that triggered the hook
$user           is the corresponding username
$host		is the corresponding hostname

Hooks can also set the variable $silent if they want to provide the
display for the event (via &print) and inhibit the default. This
is the direct equivalent of the "^" switch on ircII /on's, except
for "raw_irc".

Hooks marked with a * can also set the special variable $skip and cause
the line to be ignored by the client. This is in general a bad idea,
use $silent whenever possible. Only the hooks where this provides some
actual additional functionality have this possibility.  For "raw_irc"
this is the equivalent of "^" switch on ircII's /on raw_irc.

The following hooks are available, and get called with the following
arguments:

action		activated by a ctcp action;
		1st arg is the nick or channel it was sent to
		2nd arg is the message

ctcp	     *	activated by any ctcp, BEFORE the client parses
		and eventually answers the ctcp.
		1st arg is the nick or channel it was sent to
		2nd arg is the ctcp command
		3rd arg are the arguments

ctcp_reply	activated by ctcp replies;
		1st arg is the nick or channel it was sent to
		2nd arg is the ctcp command
		3rd arg are the arguments

dcc_chat	activated by received text over a dcc chat
		1st arg is the nick
		2nd arg is the text

dcc_request	activated by a received dcc chat or send request, and
		after the client has processed the request. this is
		the hook to use if you want to implement any kind of
		auto-dcc.
		1st arg is the type ("CHAT" or "SEND")
		2nd arg is the machine address (a 32-bit integer)
		3rd arg is the port
		for a DCC SEND offer:
		  4th arg is the file name
		  5th arg is the file lenght

input	     *	activated whenever the client wants to ask the user
		for a line through &getuserline (i.e. when you got
		disconnected, or need a new nick, or some script called
		&getuserline).
		1st arg is the "long" prompt
		2nd arg is the "short" one
		if the hook sets $skip, then &getuserline won't ask
		the user for anything, and the contents of $_ will
		be returned

invite		activated by invites;
		1st arg is the channel you're invited to

join		activated by joins;
		1st arg is the channel that $who is joining

kick		activated by kicks;
		1st arg is the nick of the person who got kicked
		2nd arg is the channel that they got kicked from
		3rd arg is the reason

leave		activated by parts;
		1st arg is the channel that $who is leaving

mode		activated by mode changes;
		1st arg is the channel or user the change applies to
		2nd arg is the mode change itself

msg		activated by msgs;
		1st arg is the message

nick		activated by nick changes
		1st arg is $who's new nick

notice		activated by notices
		1st arg is the nick or channel it was sent to
		2nd arg is the message

notify_signon	activated by a notify signon
		1st arg is the nick
		$user and $host are *not* set to anything meaningful

notify_signoff	activated by a notify signoff
		1st arg is the nick
		$user and $host are *not* set to anything meaningful

public		activated by non-ctcp messages to a channel;
		1st arg is the channel
		2nd arg is the message

raw_irc	     *	activated by any server line
		$who    is the originator (user or server)
		$user   is his username ('' if it comes from a server)
		$host   is his hostname (same comment)
		1st arg is the command
		2nd arg are the arguments

send_action	activated when we send a /me or a /de
		($who, $user and $host do not apply here)
		1st arg is the nick/channel
		2nd arg	is the action

send_dcc_chat	activated when we send text over a dcc chat
		($who, $user and $host do not apply here)
		1st arg is the nick we're sending to
		2nd arg is the text

send_text	activated when we send a /msg or speak on a channel
		($who, $user and $host do not apply here)
		1st arg is the nick/channel
		2nd arg is the msg

send_notice	activated when we send a notice
		($who, $user and $host do not apply here)
		1st arg is the nick/channel
		2nd arg is the notice

signoff		activated when someone signs off
		1st arg	is the quitting comment

topic		activated when someone changes the topic
		1st arg is the channel
		2nd arg is the new topic

<3-digit nb>  * activated by that particular server numeric reply
		1st arg is whatever the server sent after the number,
	 	unparsed (which means there's still a : in front of the
	 	last argument)


Example, which could be put into a file and /load'ed directly, of
a hook that will rejoin a channel whenever you are kicked:

~~~~~~~~~~~~~~~~~~~~~~~~~~~ [snip snip] ~~~~~~~~~~~~~~~~~~~~~~~~~~~
# auto-rejoin hook

sub hook_kicked {
  local($kicked, $where_from, $reason)=@_;
  					# local vars with the args
  if (&eq($kicked, $nick)) {		# if *we* got kicked
    &sl("JOIN $where_from");		# send a JOIN to the server
  }
}
&addhook("kick", "kicked");	  	# activate the hook

~~~~~~~~~~~~~~~~~~~~~~~~~~~ [snip snip] ~~~~~~~~~~~~~~~~~~~~~~~~~~~

Another example, to display the username and hostname with each
message:

~~~~~~~~~~~~~~~~~~~~~~~~~~~ [snip snip] ~~~~~~~~~~~~~~~~~~~~~~~~~~~
# userhost-on message hook

sub hook_uhmsg {
  &tell("[\cb${who}!${user}\@${host}\cb] $_[0]");  # print everything
  $silent=1;			# disable the default display
}
&addhook("msg", "uhmsg");	  	# activate the hook

~~~~~~~~~~~~~~~~~~~~~~~~~~~ [snip snip] ~~~~~~~~~~~~~~~~~~~~~~~~~~~

Userhost requests:

Sometimes in a function you need to know the full username and hostname 
for some nick. If this happens in a hook, and the nick is the one who 
did the action, then the nick is in $who and the userhost data is 
already in $user and $host.

Otherwise, you have to call the perl function &userhost giving it three 
arguments: the nickname, what you want evaluated when the data is 
available, and what you want evaluated if the nick is not found on IRC; 
if the third argument is ommited, sirc will print the default message 
"*?* somenickname not found on IRC".

Unlike with earlier versions of sirc, it is possible to do more than
one userhost request in a short time before getting the answers from
the server.


Example: a function that prints someone's country code

~~~~~~~~~~~~~~~~~~~~~~~~~~~ [snip snip] ~~~~~~~~~~~~~~~~~~~~~~~~~~~
# country code

sub printcountry {		# prints $host's country code

  if ($host =~ /\.([^.]+)$/) {  # match the last part of the host
    local($c)=($1); 		# put it in local var $c
    $c="USA" if $c =~ /^edu$/i;	# if it's a .edu, say it's USA
    $c="USA (probably)" if $c =~ /^com$/i || $c =~ /^org$/i || $c =~ /^net$/i;
				# if it's a .org, .com or .net, it's
				# probably in the USA too
    if ($c =~ /^\d+$/) {	# if it's a number
      &tell("*** out of luck, $who has an IP address :p");
				# complain, it's an IP
    } else {			# otherwise
      &tell("*** $who is in $c");
				# announce the result
    }
  }
}

sub cmd_country {		# this is the command

  &getarg;			# get the argument in $newarg
  if ($newarg) {		# if it's there
    &userhost($newarg, "&printcountry;");
				# request a userhost with &printcountry as
				# action to take
  } else {			# otherwise
    &tell("*** Whose?");	# complain
  }
}

&addcmd("country");		# install the command

~~~~~~~~~~~~~~~~~~~~~~~~~~~ [snip snip] ~~~~~~~~~~~~~~~~~~~~~~~~~~~


Timers:

It is possible in sirc to specify an action to be done but delayed, a 
certain number of seconds later, just like with ircII's /timer function.
This is only precise up to the second.

To do this, you call the function &timer with the number of seconds to 
wait as the first argument, and the string to be evaluated as the second 
argument.

This is simple enough, but if you really need an example, here comes:
to print "hello" in 10 seconds, you'd do &timer(10, "&tell('hello')");



Bots:

It is possible to make bots in sirc script, just like you make bots in 
ircII. It's even probably not a bad idea, since you have a proper and 
powerful programming language (perl) at your disposition, with all the 
boring network programming and parsing of server stuff already done for 
you.

However, sirc was never meant as a bot client, and I have no intention
of filling it up with bells and whistles for bot support, so I've only
provided minimal support for this, with the -l and -q options.

The idea is, you program your bot as a set of internal functions and
hooks and a calls to &addhook and to &docommand, and then load the sirc
this way (obviously without ssfe):

nohup sirc -d -q -l <botfile> -i <bot's ircname> <nick> <server> >/dev/null &

All of this without the <>'s, of course. The >/dev/null is there to
suppress the output, since you won't be reading it on the screen
anyway.

In the bot, make sure you catch (with a numeric hook) the lines that 
tell "nick in use" or "invalid nick", and send lines to the server with 
some random nick, and get them skipped, or the bot will freeze trying to 
ask the user for a nick. You should also set up a hook on "input", and 
make it returns a server name in $_ and set $skip, since &getuserline 
gets called whenever the current server connection is lost.

Also remember that the file gets loaded even before the server connection
is made, so calls to &sl and most &docommand's at that point will fail.

Here's an example of a bot that connects, joins a channel, reconnects if 
disconnected, responds to a few commands, ops its owner, and logs all it 
sees except public stuff to a file; you'd load this one, assuming you 
saved it in a file called "mybot" and want to call it BubbleBot, with:

nohup sirc -d -q -l mybot -i "bot in sirc" BubbleBot some.server.edu >/dev/null


~~~~~~~~~~~~~~~~~~~~~~~~~~~ [snip snip] ~~~~~~~~~~~~~~~~~~~~~~~~~~~
$botowner="espel\@clipper.ens.fr";	# change it to your address

$logfile=$ENV{'HOME'}."/.botlog";
&docommand("log on");

sub hook_publicstuff {		# don't print the public stuff (so it
  $silent=1;			# doesn't fill the logfile
}
&addhook("public", "publicstuff");

sub hook_connected {
  &sl("JOIN #BotTub");
}
&addhook("376", "connected");   # join on the "end of MOTD" numeric

srand;				# init random number generator

sub hook_badnick {
  local($n);
  $n="B".(int(rand(1000000))+4587454);  # send a garbage nick...
  &sl("NICK $n");
  $skip=1;
}
&addhook("432", "badnick");             # if told that ours is taken
&addhook("433", "badnick");

sub hook_input {        # if asked for a line, it means we got disconnected
                        # (since we've caught the badnick thing)
  sleep(30);		# wait 30 seconds (so we don't bring the machine
  			# down to a crawl if the server is down)
  $_="0";               # return '0' : reconnect to the initial server
  $skip=1;		# and don't actually ask for a line
}
&addhook("input", "input");

sub hook_joined {	# whenever someone joins
  local($ch)=($_[0]);
  $ch =~ tr/A-Z/a-z/;	# put channel in lowercase
  if (&eq($botowner, "$user\@$host") && $haveops{$ch}) {
    &sl("MODE $ch +o $who");	# op if that's the owner and we have ops
  }
}
&addhook("join", "joined");

sub hook_message {
  if (&eq($botowner, "$user\@$host")) {  # if it's a msg from the owner
    if ($_[0] =~ /^die$/i) {             # die -> die
      &docommand("quit");
    } elsif ($_[0] =~ /^say /i) {        # say <something> -> say it
      &say($');
    } elsif ($_[0] =~ /^nick /i) {       # nick <nick> -> change nicks
      &sl("NICK $'");
    }
# add more commands here
  }
}
&addhook("msg", "message");

~~~~~~~~~~~~~~~~~~~~~~~~~~~ [snip snip] ~~~~~~~~~~~~~~~~~~~~~~~~~~~

